1. Field of the Invention
The present invention relates to computer hardware components. More specifically, the present invention provides an apparatus for directing power to a hot-swappable computer component when inserted, and safely powering down the component prior to removal.
2. Description of the Related Art
Hot swappable components have become commonplace in computer systems. Server systems often use hot swappable memory, hard drives, and various pieces of hardware commonly referred to as Peripheral Component Interconnect (PCI) cards. Hot swapping may involve the removal of a piece of hardware, or the insertion of a piece of hardware, or both while the computer is on and functioning. While the following discussion refers to PCI cards, the problems presented are equally applicable to any other hot swappable electronic circuit board.
Computer systems that support hot swapping need some ability to detect that a component has been removed or inserted and to determine what resources are available for use. Notifying the system that a component has been inserted or removed allows for efficient allocation of resources and the use of computing power.
In addition, all connections need to be designed such that neither the component nor the user can be damaged or injured by removing or installing it. Most, if not all, computer components require power to be operational. The electronic connections between components must be designed to ensure that connecting the components will not result in a power surge to either component, which may result in damage to sensitive electronics.
The components of the computer system must be designed to accommodate removal or installation of other components. When a component is removed, the computer system must reallocate tasks to other components. When a component is inserted, the system must be able to allocate tasks to that component in order to make the most efficient use of the system resources.
One method of inserting a PCI card is to utilize a cassette system in which the PCI card with a connector is secured. The cassette may then be inserted into a chassis wherein a connection is made between the PCI card within the cassette, and other pieces of hardware with receiving connectors.
Many PCI cards receive power from the connector in which they are inserted. In order to avoid power surges and damage to the PCI card or the user, it is preferable that no power is being provided to a receiving connector during insertion or removal of a PCI card. Future implementations of operating system software may require that no power is provided to the receiving connector during insertion or removal of a PCI card.
Therefore, there is a need for an apparatus and method to ensure that no power is provided during removal of a PCI card, as well as preventing power to the PCI card during insertion. When a cassette system is employed to insert and remove electronics, it is desirable to incorporate this feature into the cassette.